Today, the structural study of complex glycoconjugates is possible because of recent technical advancements. Through this kind of studies, important biological roles have merged for these molecules. This analyses require very expensive instrumentation, highly trained personnel and a considerable amount of time. Therefore, the availability of a core service with all these requirements will put the Program Project investigators in the best possible situation to exploit today's technology the systems under study. The Glycobiology Core (Core) will help address all questions regarding the carbohydrates present in a given system. The close interaction between the Core Director and every P.I. in the Project will result in the design of the most adequate protocols for the isolation/purification of samples in order to obtain optimum results in the characterization of their carbohydrates. The Core will offer all general services, such as: 1) Enzymes, Reagents and Protocols, for addressing specific questions regarding carbohydrates; 2) Metabolic labelling compounds. The Core can also synthesize and purify labelled molecules required for a specific purpose that are not commercially available and/or that are very expensive or not reliable; 3) Standards; 4) Low Resolution Oligosaccharide Analyses, total carbohydrate compositions, or analysis for the presence of specific sugars (e.g. sialic acids), and permethylation analysis to determine linkage positions; 5) Literature Reference Data Base and Specific Protocols, searches for references or protocols for specific purposes; 6) CarbBank Data Base Searches, for specific carbohydrate structures; 7) Molecular modelling of oligosaccharides 8) Fast-Atom Bombardment Mass Spectrometry (FAB-MS), to determine molecular weight and type of structure (branching, presence of substituents, etc.) of a pure oligosaccharide or glycoconjugate, or mixtures of them. Several specific services for projects in the Program have been already planned, and others will be provided as they become necessary. For most of the projects in this Program, the limited amount of material available will determine the use of HPLC techniques with radiochemical detection. However, we predict that most other methods for structural characterization will be useful since these techniques are now sensitive in the femtomole to picomole range. A set os standardize methods for the analysis of carbohydrates will be used. Specific techniques used will depend on the structural characteristics to be addressed, and any available methodology to solve these problems will be considered. Particularly, when no available methodology is adequate to address a specific question, the development of a new method will be considered.